Abrasive-resisting metal and process for making same



Patented Mar. 13, 1928 UNITED STATES 1,662,357 PATENT OFFICE.

LABBY J. BARTON, 01 MOGILL, NEVADA.

- ABBASIVE-RESISTING METAL AND PROCESS FOR MAKING No Drawing.

My invention relates to an improvement in the composition of resistant-surface or abrasivc-resistingalloys and castings and to the process of making such alloys and castings. One of the objects is to create a cheaper and better substitute for the metals and alloys used to make abrasive-resisting castin s, including man anese steel, heat treatedc irome steels and w ite irons, at the present time. It is intended for use in producing castings where resistance to abrasion is paramount in importance such as are used in mining, cement making, brick makin in the lime, pottery and porcelain indus ries, in crushing rocks or sand or in any use where grinding or pulverizing is necessary.

A further object of m invention is to produce alloy castin w ich are chea and which can be used in their un-anneale state. It aims to produce castings which will not chip or flake when in service and which will be free from blow holes, due to gases within the metal, which weaken their structure. The metals which are the object of my invention should have the ualities, in their un-annealed state, of toug ness, of a dense structure and high molecular cohesiveness and which will not chip, flake, or crack in service. While only certain uses and forms of my invention are described, the equivalents and means by which the same results are obtained are within the contemplation of m invention.

ile the means of arriving at the particular analyses of the alloys is of special importance, I have made the composition of the metal as follows: iron from 98.22 to 97.02 per cent, carbon from 0.80 to 1.30 per cent, silicon from 0.30 to 0.60 per cent, manganese from 0.60 to 1.00 per cent, sulphur and phosphorus less than 0.08 per cent.

Another type of this alloy contains the element chromium and makes the analysis of the metal as follows: iron from 97.72 to 94.02 per cent, carbon from 0.80 to 1.30 per cent, SlllCOIl from 0.30 to 0.60 per cent, manganese from 0.60 to 1.00 per cent, chromium from 0.50 to 3.00 per cent, sulphur and phosphorus less than 0.08 per cent. With the chromium content the metal becomes harder than the alloy without it. For largevcastings the maximum chromium content is used and for small ones or those of intricate shape and with a tendency to crack a lower chromium content is preferable.

To obtain these alloys from materials ished castings.

Application filed September 1, 1926. Serial No. 133,081.

which arefcheap and abundant and in such a way that the resulting analysis of the metal will be correct is the function of the procedure hereinafter described.

acidined electric furnace and melted. To this is added sufiicient material of a carbonaceous nature such as coke, coal, charcoal, or similar substances to brin the carbon content of the mixture to t e desired point. After this has been thoroughly heated and melted slag material such as old molding sand, new sand, crushed brick or any similar siliceous material is added in sufficient quantities to form a'coating over the bath from 00 An grade of steel scrap is charged into an oneuarter to one-half inch in depth. When slag is in its best reducing condition and rapidly eliminates the gases from the metal according to the assumed reaction:

SiO FeO 3C FeSi 300 SiO -l-MnO 3C'==MnSi+ 300 The gases within the metal are by this means absorbed and the metal becomes free of the prime causes of blow holes in the fin- The main function of the slag in this condition, however, is to introduce silicon into the metal in its nascent con dition without using ferro-silicon which, in addition to being expensive, is more diificult to handle in that it becomes mingled with the slag and rabbling is necessary in order to force the silicon into the metal. The latter process inevitably causes a certain amount of slag to become mixed up in the metal and results in an impure metal. If the metal is not yet' hot enough to pour, lime or any oxidizing material is mixed with the slag in order to absorb the added silicon from the continued reducing action of the slag due to the resulting equation:.

4 FeO SiO =FeSi+ 30 If the metal is hot enough to pour, when the reducing action of the ag is at its maximum, form-manganese is added in quantities of from 0.80 to 1.50 per cent, which absorbs the oxygen released by the slag reduction and goes into combination with the slag. This term-manganese is not used as a primary reducing agent as customary in acid electric operation but as a means of eliminating the remaining free oxy en after sufficient silicon has been inserted into the metal. It further acts as a check on the silicon re duction and prohibits the customary silicon reduction at the expense of carbon in the metal because the manganese oxide must first be reduced before the silicon. Unless this were done, the released oxygen would be dissolved in the metal and result in gas holes in the finished castings. The chemical reaction of the addition of the ferro-manganese is as follows:

FeSi O 3Mn= FeSi 3MnO Thereupon the alloy is poured into the ladies and, while being poured, from 0.30 to 0.60 per cent silicon in the form of crushed ferro-silicon is added. The value of the latter and in such percentages lies in the durability which it gives to the alloy and as a prevention against the absorption of oxygen or other gases while the metal is being poured into molds.

As a further precaution against the absorption of gases by the alloy before it attains its solid state small pieces of aluminum are added when the metal is being poured into the molds to absorb any gases present in the molds.

When a metal is desired which is still harder, ferro-chrome in quantities ranging from 0.50 to 3.00 per cent is added to the metal in the ladle. As previously mentioned the amount of ferro-chrome added depends on the nature of the castings to be made, a greater amount being used for large, heavy castings than for small ones or those of intricate shapes.

The metals produced by this process and in this way can be poured either in sand or chill molds and the finished castings have the same characteristics when produced either way. This is due to the fact that the metals contain carbon in such a state that there is no added chilling effect from an iron mold.

Furthermore the castings when made are used in their raw and un-annealed condition, thereby saving in cost by eliminating all heat treating operations, inasmuch as the castings after cooling in their molds are tough, with high molecular cohesiveness, thereby insuring wearing qualities without being hard and brittle.

What I claim is:

1. The process of making an alloy comosed, in combination with the iron, of car- [ion from 0.80 to 1.30 per cent, of silicon from 0.30 to 0.60 per cent, of manganese from 0.60 lo 1.00 per cent, and of sulphur and phosphorus not exceeding 0.08 per cent, nhich consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentage; in adding sand or other siliceous material to form a coating of sla from one'qunrtcr to one-half inch; in adding lime to make said slag fluid; in adding lime, siliceous material, cast iron. pig iron, term-manganese or manganese steel scrap in small quantities until said slag becomes a yellowish-green in color, whereby gases are eliminated from and silicon is absorbed by said alloy; in adding ferro-manganese in quantity from 0.80 to 1.50 per cent, whereby oxygen is absorbed from said metal; in adding from 0.30 to 0.60 per cent crushed term-silicon; and in adding small pieces of aluminum as said alloy is being poured into molds whereby gases present in said molds are absorbed.

2. The process of making an alloy composed, in combination with the iron, of carbon from 0.80 to 1.00 per cent, of silicon from 0.30 to 0.60 per cent, of manganese from 0.60 to 1.00 per cent, of chromium from 0.50 to 3.00 per cent, and of sulphur and phosphorus not exceeding 0.08 per cent, which consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentages: in adding sand or. other siliceous material to form a coating of slag from onequarter to one-half inch; in adding lime to make said slag fluid; in adding lime, siliceous material, cast iron, pig iron, ferromanganese or manganese steel scrap in small quantities until said slag becomes a yellowish-green in color, whereby gases are eliminated from and silicon is absorbed by said alloy; in adding term-manganese in quantity from 0.80 to 1.50 per cent, whereby oxygen is absorbed from said metal: in adding from 0.30 to 0.60 per cent crushed ferro-silicon; in adding ferro-chrome in the desired percentages; and in adding small pieces of aluminum as said alloy is being poured into molds whereby gases present therein are absorbed.

3. The process of making an alloy composed, in combination with the iron. of carbon, silicon, manganese, sulphur and phos phorus in desired proportions which consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentages; in adding sand or other siliceous materials to form a coating of slag from one-quarter to onehalf inch; in adding lime to make said slag fluid; in adding lime, siliceous material, cast iron, pig iron, ferro-manganese or manganese steel scrap in small quantities until said slag becomes yellowish-green in color, whereby gases are eliminated from and silicon forced into said alloy; and in adding ferro-silicon in the desired proportion to further absorb oxy en.

4. The process 0 making an alloy comosed, in combination with the iron, of car- I n, silicon, manganese, sulphur and phos phorus, and chromium in desired proportions which consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentages; in adding. sand 'or other siliceous material to form a coating of slag fronr the iron, of carbon, silicon, manganese, sulphur and phosphorus in desired proportions which consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentage; in adding sand or other siliceous material to form a coating of slag from one-quarter to one-half inch; in adding lime to make said slag fluid; in adding lime, siliceous material, cast iron, pig iron, ferro-manganesc or manganese steel scrap in small quantities until said slag becomes yellowish-green in color whereby gases are eliminated from said alloy and silicon forced into it; in adding ferro-manganese in greater quantities whereby 0x gen is further absorbed; and in adding erro-silicon in the desired percentage.

6. The process of making a resistant-surface alloy composed, in combination with the iron of carbon, silicon, manganese, sulphur and phosphorus and chromium in desired proportions, which consists in melting steel scrap in an acid-lined electric furnace;

in adding carbonaceous material in the desired percentage; in adding sand or other siliceous material to form a coating of slag from one-quarter to one-half inch; in adding lime to make said slag fluid; in working.

said slag with lime, siliceous material, cast iron, plg iron, ferro-manganese or manganese steel scrap in small quantities until said slag becomes yellowish-green in color whereby gases are eliminatedfrom said alloy and silicon forced into it; in adding ferro-manganese in greater quantities whereby oxygen is further absorbed; in adding ferro-silicon in thedesired percentages; and in adding chromium in the desired proportion whereby the structure of the alloy is further hardened.

7. The process of making abrasive-resisting castings of an alloy composed in com bination with the iron, of carbon, silicon, manganese, sulphur and phosphorus in desired proportions, which consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentages; in adding sand or other siliceous material to form a coating of slag from one quarter to one-half inch; in adding lime to make said slag fluid; in adding lime, siliceous material, cast iron, pi g iron, form-manganese or manganese steel scrap in small quantities until said slag becomes yellowish-green in color whereby gases are eliminated from said alloy and silicon forced into it; in adding ferro-manganese in greater quantities; whereby oxygen is further absorbed; in adding crushed ferro-silicon in the desired percentages; and in adding small quantities of aluminum as said alloy is being poured into molds whereby gases therein are absorbed.

8. The process of making abrasive-resisting castings of an allo composed, in combination with the iron, oi carbon, silicon, manganese, sulphur and phosphorus, and chromium, in desired proportions, which consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentages; in adding sand or other siliceous material to form a coating of slag from one-quarter to one-half inch; in adding lime to make said slag fluid; in adding lime, siliceous material, cast iron, pig iron, ferro-manganese or manganese steel scrap in small quantities until said slag becomes yellowishreen in color whereby gases are eliminated rom said alloy and silicon forced into it; in adding ferro-manganese in greater quantities whereby oxygen is further absorbed; in adding ferro-silicon in the desired quantity; in adding chromium in the desired proportion; and in adding small quantities of aluminum as said alloy is being poured into molds whereby gases therein are absorbed. 1

9. The process of making abrasive-resisting castings of an alloy composed, in combination with the iron, of carbon from 0.80 to 1.30 per cent; of silicon from 0.30 to 0.60 per cent; of man anese from 0.60. to 1.00 per cent; and of su phur and phosphorus not exceeding 0.08 per cent; which consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentage; in adding sand or other siliceous material, to form a coating ofv slag from one-quarter to one-half inch; in adding lime to make said slag fluid; in working said slag with lime, siliceous ma terial, cast iron, ig iron, form-manganese or manganese stee scrap in small quantities until said slag becomes yellowish-green in color whereby gases are eliminated from and silicon forced into said alloy; in adding from 0.80 to 1.50 per cent manganese whereby oxygen is further absorbed; in adding from 0.30 to 0.60 per cent crushed ferro-silicon as said alloy is being poured; and in adding-small pieces of aluminum to the molten metal in the molds whereby gases therein are absorbed.

10. The process of making ahrasivemesisting castings of an alloy composed, in combination with the iron, of carbon from 0.80 to 1.30 per cent, of silicon from 0.30 to 0.00 per cent, of manganese from 0.00 to 1.00 per cent, of sulphur and phosphorus notexceeding 0.08 per cent, and of chromium from 0.50 to 3.00 per cent, which consists in melting steel scrap in an acid-lined electric furnace; in adding carbonaceous material in the desired percentage; in adding sand or other siliceous material to form a coating of slag from one-quarter to one-half inch; in addin lime to make said slag fluid; in working said slag with lime, siliceous material, cast iron, pig iron, ferro-manganese or manganese steel scrap in small quantities until said slag becomes yellowish-green in color whereby gases are eliminated from and silicon forced into said alloy; in adding from 0.80 to 1.50 per cent term-manganese whereby oxygen is further absorbed; in adding from 0.30 to 0.60 per cent crushed form-silicon and from 0.50 to 3.00 per cent term-chrome as said alloy is being poured; and in adding small-pieces of aluminum to the molten metal in the molds whereby gases therein are absorbed.

Signed by me this 14th day of August. 1926.

LARRY J. BARTON. 

